Background Hidradenitis suppurativa (HS), also referred to as acne inversa, is a debilitating skin disease characterized by inflammatory nodules, chronic abscesses and tunnels (fistulae and sinuses). The association with pilonidal sinus disease (PSD) is frequently reported but not well documented. Objectives To determine the prevalence and characteristics of inflammatory skin lesions located in the intergluteal fold (IGF) of patients with HS. Methods This was an international multicentre retrospective cross-sectional study based on data collection from a large cohort of patients with HS with and without histopathology. Results From a total of 2465 patients with HS included in the study, 661 (27%) reported lesions in the IGF. These patients were significantly more often smokers and had more severe HS. Of the 238 patients with an available clinical diagnosis, intergluteal-HS (IG-HS) was diagnosed in 52 patients (22%) and PSD was diagnosed in 186 patients (78%). IG-HS was associated with the localization of HS in the proximity of the IGF, including the buttocks, genitals and the anus. There was a possibility of misclassification bias in this study as a clinical/image-based diagnosis or histopathology of the IGF lesions was not always available. Conclusions The high prevalence of PSD suggests a strong link between both entities. Therefore, it may be useful to identify common pathophysiological mechanisms and develop common therapeutic strategies.

doi.org/10.1111/bjd.17927, hdl.handle.net/1765/123320
British Journal of Dermatology
Department of Dermatology

Benhadou, F, van der Zee, H., Pascual, J.C., Rigopoulos, D., Katoulis, A., Liakou, A.I., … Guillem, P. (2019). Pilonidal sinus disease: an intergluteal localization of hidradenitis suppurativa/acne inversa: a cross-sectional study among 2465 patients. British Journal of Dermatology, 181(6), 1198–1206. doi:10.1111/bjd.17927